3种功能性甜味剂对大米蒸煮品质和消化特性的影响

为提高米饭蒸煮品质、延缓米饭回生和改善米饭消化性能，比较不同质量分数低聚果糖、山梨糖醇和麦芽糖醇3 种低能量甜味剂对大米浸泡吸水率、直链淀粉比例、硬度、微观结构、晶体结构、热特性及消化特性等指标的影响。结果表明，3 种甜味剂处理均能够提高大米的吸水率，降低米饭的硬度。此外，低聚果糖、山梨糖醇和麦芽糖醇处理均能降低米饭的体外消化水解率。其中，1.6%低聚果糖处理的大米在浸泡25 min时吸水率提高了11.18%，直链淀粉比例、糊化焓值和放置24 h后硬度分别降低了7.36%、22.91%和21.79%，且与其他处理相比，显著降低了糊化焓值和结晶度，并表现出较好的微观结构和抗回生性。该研究为大米精深加工与方便米饭产品开发提供依据。

Effects of Three Functional Sweeteners on Cooking Quality and Digestion Characteristics of Rice

In order to improve the cooking quality of rice, to retard the retrogradation of cooked rice and to improve the digestibility of cooked rice, we evaluated the effects of three low-energy sweeteners of fructo-oligosaccharide, sorbitol and maltitol at different concentrations on the water absorption rate and the proportion of amylase in raw rice, as well as the hardness, microstructure, thermal characteristics and digestibility of cooked rice. The results showed that all the three sweeteners could improve the water absorption capacity of raw rice and reduce the hardness and digestibility in vitro of cooked rice. The water absorption rate after 25 min immersion was 11.18% higher in 1.6% fructo-oligosaccharide solution than in blank control, and the proportion of amylose, gelatinization enthalpy and hardness after 24 h decreased by 7.36%, 22.91% and 21.79%, respectively. Compared with the other treatments, 1.6% fructo-oligosaccharide treatment significantly reduced gelatinization enthalpy and crystallinity, and showed better microstructure and anti-retrogradation ability. This study provides a basis for deep processing of rice and the development of instant rice products.